How to Manage Pests

Pests in Gardens and Landscapes

Parasites

Insect parasites (parasitoids) are smaller than their hosts and develop inside, or attached to the outside, of the host's body. Often, only the immature stage of the parasite feeds on the host, and it kills only one host during its development. Many caterpillar eggs are destroyed by tiny parasitic wasps. Most larvae are attacked by one or more larger species of wasp. For example, redhumped caterpillar larvae are attacked by two common parasitic wasps, Hyposoter fugitius and Apanteles sp.

A female Hyposoter wasp injects an egg into an early instar caterpillar; the egg hatches into a larva that feeds on the body fluids and tissues of the host. The host dies in the third or fourth instar, and the Hyposoter larva emerges from the host's body, spins a cocoon, and pupates. The adult wasp emerges from the cocoon to mate and seek new hosts; each female may destroy up to 100 host caterpillars. The life cycle takes as few as 15 days, depending on temperature.

Apanteles cocoons
Apanteles cocoons

 

Life cycle of a Hyposoter parasite
Life cycle of a Hyposoter parasite

Redhumped caterpillars parasitized by Hyposoter  wasps
Redhumped caterpillars parasitized by Hyposoter wasps


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